I spent a day in the rain yesterday visiting a few burial chambers in Anglesey. Most of them had the stones exposed but the last one, Bryn Celli Ddu, has an earth mound over it. I understand that most, if not all, were originally covered. The exposed stones do look very impressive but a simpler and easier solution could have been adopted if their purpose was simply to create a void in the mound. Some of the stones weigh several tonnes. Any thoughts from anyone regarding this? Maybe the stones weren’t covered initially?